[UPMERGE] 1.7 -> 2.0 (Sylius#422)

This PR has been generated automatically.
For more details see
[upmerge_pr.yaml](/Sylius/PayPalPlugin/blob/1.7/.github/workflows/upmerge_pr.yaml).

**Remember!** The upmerge should always be merged with using `Merge pull
request` button.

In case of conflicts, please resolve them manually with usign the
following commands:
```
git fetch upstream
gh pr checkout <this-pr-number>
git merge upstream/2.0 -m "Resolve conflicts between 1.7 and 2.0"
```

If you use other name for the upstream remote, please replace `upstream`
with the name of your remote pointing to the `Sylius/PayPalPlugin`
repository.

Once the conflicts are resolved, please run `git merge --continue` and
push the changes to this PR.

Author: NoResponseMate

.gitattributes

@@ -0,0 +1,19 @@
+/.github                        export-ignore
+/etc                            export-ignore
+/spec                           export-ignore
+/tests/DataFixtures             export-ignore
+/tests/DependencyInjection      export-ignore
+/tests/Integration              export-ignore
+/tests/Service                  export-ignore
+/tests/TestApplication          export-ignore
+/tests/Unit                     export-ignore
+.editorconfig                   export-ignore
+.gitattributes                  export-ignore
+.gitignore                      export-ignore
+behat.yml.dist                  export-ignore
+ecs.php                         export-ignore
+node_modules                    export-ignore
+phpstan.neon.dist               export-ignore
+phpunit.xml.dist                export-ignore
+rector.php                      export-ignore
+symfony.lock                    export-ignore

.gitignore

@@ -8,7 +8,6 @@
 
 /.phpunit.result.cache
 /behat.yml
-/phpspec.yml
 /phpunit.xml
 
 /tests/TestApplication/.env.local